To resolve a kind of node Mura of 116.8 cm(46 in) Fringe Field Switching panel in array actual 4mask etching process

scanning electron microscopy

focused ion beam

energy dispersive spectroscopy Macro/Micro and critical dimension are used to verify the compositions and crystals. Also GI test

PVX layer's front and backside in 1% HF corrosion experiment

elevating 10℃ in lower electrode

varying ash and AT(after treatment)of n

+

step and active BT conditions are carried out. In addition

the effect of the n

+

doped a-Si thickness is studied. So the Mura sources

influencing factors and the Mura mechanism are revealed:First factor is its first formation on the substrate back scratch

the other is the film changes between contact and non-contact electrode layer etching regional in temperature changes

the third is by-products adhesion to the substrate backside in active layer dry etch

followed by a multi-layer film deposition and amplified after wet etch-strip process. Finally the flat and rough lower electrode is adopted

remaining a-Si thickness is restricted between 210 nm and 230 nm

and temperature is elevated to 50℃

then node Mura has not been found and the overall Mura ratio is less than 0.08%.